Commonly used nonaqueous electrolytes for electrochemical devices such as lithium ion secondary batteries are electrolytes containing an electrolyte salt (e.g., LiPF6, LiBF4) dissolved in a nonaqueous solvent (e.g., ethylene carbonate, propylene carbonate, dimethyl carbonate). Such hydrocarbon solvents, however, have a low oxidation potential, and therefore the electrolyte may be decomposed in high voltage batteries produced in the future.
Patent Literature 1 discloses that a nonaqueous electrolyte secondary battery including a fluorinated linear carbonate suppresses gassing caused by electrodialysis and is highly safe. Patent Literature 1, however, does not mention about impurities of the compound. In addition, such a nonaqueous electrolyte secondary battery may have its discharge capacity lowered when left in a high-temperature environment or after repetitive charge-discharge cycles.